Method for transmitting positioning assistance data and device

ABSTRACT

Embodiments of this application provide a method for transmitting positioning assistance data and a device. The method includes: receiving, by a network device, at least one positioning assistance data message sent by a positioning server, where the at least one positioning assistance data message is used to carry positioning assistance data; and broadcasting, by the network device, a system message to a terminal device, where the system message is used by the terminal device to obtain the positioning assistance data. According to the embodiments of this application, the network device broadcasts the system message to broadcast the positioning assistance data.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/369,386, filed on Mar. 29, 2019, which is a continuation ofInternational Application No. PCT/CN2017/081897, filed on Apr. 25, 2017,which claims priority to International Patent Application No.PCT/CN2016/101403, filed on Sep. 30, 2016. All of the afore-mentionedpatent applications are hereby incorporated by reference in theirentireties.

TECHNICAL FIELD

Embodiments of this application relate to the communications field, andin particular, to a method for transmitting positioning assistance dataand a device.

BACKGROUND

In an existing 3rd Generation Partnership Project (3GPP) positioningtechnology, a point-to-point protocol is usually used to support apositioning service. For example, the point-to-point protocol is theLong Term Evolution Positioning Protocol (LPP). In the LPP protocol, apositioning server provides positioning assistance data for a terminaldevice in point-to-point unicast mode.

In a scenario in which there are a large quantity of connections or alarge quantity of positioning requests, using the solution oftransmitting the positioning assistance data in point-to-point unicastmode causes relatively low efficiency of transmitting the positioningassistance data.

Therefore, how to improve the efficiency of transmitting the positioningassistance data has become a problem that urgently needs to be resolved.

SUMMARY

Embodiments of this application provide a method for transmittingpositioning assistance data, a network device, a positioning server, anda terminal device. The method can improve efficiency of transmittingpositioning assistance data.

According to a first aspect, a method for transmitting positioningassistance data is provided. The method includes: receiving, by anetwork device, at least one positioning assistance data message sent bya positioning server, where the at least one positioning assistance datamessage is used to carry positioning assistance data; and broadcasting,by the network device to a terminal device, a system message carrying atleast one first parameter, where each first parameter is used by theterminal device to detect first indication information at a firstresource location, and the first indication information is used toindicate a second resource location at which the network device is tosend the positioning assistance data.

Therefore, in this embodiment of this application, the network devicebroadcasts the message to broadcast the positioning assistance data. Inthis way, a problem of low efficiency of transmitting existingcentralized positioning assistance data can be resolved, and a problemin the prior art that a positioning server needs to perform signalingcommunication with each terminal device in a unicast transmissionscenario can be avoided, thereby reducing signaling overheads.

In an implementation of the first aspect, the method further includes:sending, by the network device, the first indication information at thefirst resource location; and sending, by the network device, thepositioning assistance data at the second resource location.

Therefore, in this embodiment of this application, the network devicesends the positioning assistance data to the terminal device by usingthree steps. First parameter information having a relatively small datavolume may be added to the system message to reduce a size of the systemmessage. In addition, the first indication information may be detectedon a predefined resource by using the first parameter, to reducesignaling overheads on a second resource. In this way, a problem of lowefficiency of transmitting existing centralized positioning assistancedata can be resolved, and a problem in the prior art that a positioningserver needs to perform signaling communication with each terminaldevice in a unicast transmission scenario can be avoided, therebyreducing signaling overheads.

For example, when a positioning assistance data packet is relativelysmall, the positioning server may send a positioning assistance datamessage to the network device, where the positioning assistance datamessage carries the positioning assistance data.

Therefore, in this embodiment of this application, the positioningassistance data can be sent by using only one positioning assistancedata message, thereby reducing signaling overheads and providing systemperformance.

In an implementation of the first aspect, when the positioningassistance data includes at least two pieces of positioning assistancesubdata, that the at least one positioning assistance data message isused to carry positioning assistance data includes: each positioningassistance data message carries one piece of positioning assistancesubdata.

For example, when a positioning assistance data packet is relativelylarge, the positioning server may send N positioning assistance datamessages to the network device, where N is an integer greater than orequal to 2, and the N positioning assistance data messages are used tocarry the positioning assistance data.

Specifically, the positioning assistance data may include N pieces ofpositioning assistance subdata, and the positioning assistance datamessage includes N positioning assistance subdata messages.

The receiving, by a network device, a positioning assistance datamessage sent by a positioning server includes: receiving, by the networkdevice, the N positioning assistance subdata messages sent by thepositioning server, where each of the N positioning assistance subdatamessages carries one of the N pieces of positioning assistance subdata.

It should be understood that in this embodiment of this application,data volumes of the N pieces of positioning assistance subdata may beapproximately equal or may not be equal. The positioning server maydetermine an amount of each piece of positioning assistance subdatadepending on an actual situation. This is not limited in this embodimentof this application.

Therefore, in this embodiment of this application, when the positioningassistance data is relatively large, the positioning assistance data maybe sent by using a plurality of positioning assistance data messages, toavoid generation of an excessively large message. In addition, whentransmission of a positioning assistance data message fails, only thepositioning assistance data message of which transmission fails needs tobe retransmitted, thereby reducing a quantity of data retransmissionsand improving system performance.

For example, the first parameter is used by the terminal device todetect second indication information at the first resource location, andthe second indication information is used to instruct the network deviceto transmit a third resource location for sending the positioningassistance data.

Specifically, the first parameter may be a positioning radio networktemporary identifier (RNTI), the second resource location may be alocation of a physical downlink control channel (PDCCH) resource, thesecond indication information may be downlink control information (DCI)borne on the PDCCH, and the third resource location may be a location ofa physical downlink shared channel (PDSCH) resource. The PDCCH may be aPDCCH resource in one of the foregoing plurality of network systems towhich this embodiment of this application can be applied. The PDSCH maybe a PDSCH resource in one of the foregoing plurality of network systemsto which this embodiment of this application can be applied.

It should be noted that the at least one first parameter in thisembodiment of this application may include one parameter or may includea plurality of parameters. For example, the first parameter may includea plurality of (groups of) positioning RNTIs, and each (group of)positioning RNTI corresponds to one positioning method or one mode ofone positioning method. For example, a positioning RNTI 1 corresponds toan OTDOA method, and a positioning RNTI 2 corresponds to an A-GNSSmethod.

When the first parameter in this embodiment of this application includesone (group of) positioning RNTI, the terminal completes subsequentreceiving by using the (group of) obtained positioning RNTI. The (groupof) positioning RNTI corresponds to one positioning method, for example,an OTDOA cellular positioning method or GPS satellite positioning.

When the first parameter in this embodiment of this application includestwo (groups of) positioning RNTIs, the terminal completes subsequentreceiving by using the obtained two (groups of) different positioningRNTIs. The two (groups of) different positioning RNTIs correspond to twodifferent positioning methods, for example, OTDOA and GPS satellitepositioning.

When the first parameter in this embodiment of this application includestwo (groups of) positioning RNTIs, the terminal completes subsequentreceiving by using the obtained two (groups of) different positioningRNTIs. The two (groups of) different positioning RNTIs correspond to twodifferent modes of one positioning method, for example, GPS satellitepositioning and BeiDou satellite positioning.

When the first parameter in this embodiment of this application includesthree (groups of) positioning RNTIs, the terminal completes subsequentreceiving by using the obtained three (groups of) different positioningRNTIs. The three (groups of) different positioning RNTIs correspond totwo positioning methods and two different modes of one of the twopositioning methods, for example, OTDOA cellular positioning, GPSsatellite positioning, and BeiDou satellite positioning.

Specifically, each positioning RNTI corresponds to one PDCCH resource,and DCI borne on the PDCCH resource indicates a PDSCH resource bearing acorresponding positioning assistance data.

Herein, the grouping may be performed according to different positioningmethods, different modes corresponding to a positioning method, or acombination thereof. This embodiment of this application is not limitedthereto.

Optionally, before the receiving, by a network device, a positioningassistance data message sent by a positioning server, the method furtherincludes: receiving, by the network device, a request message sent bythe positioning server, where the request message is used to request thenetwork device to forward the positioning assistance data; and sending,by the network device, a response acknowledgement message to thepositioning server, where the response acknowledgement message is usedto indicate whether the network device accepts forwarding of thepositioning assistance data.

The receiving, by a network device, a positioning assistance datamessage sent by a positioning server includes: when the responseacknowledgement message is used to indicate that the network deviceaccepts forwarding of the positioning assistance data, receiving, by thenetwork device, the positioning assistance data message sent by thepositioning server.

Therefore, in this embodiment of this application, the positioningserver can send the positioning assistance data to the network deviceonly when the request is accepted. Compared with a case in which thereis no request, a response of the network device can be received when therequest is not accepted, thereby avoiding unnecessary transmission andavoiding a waste of resources.

Alternatively, when the response acknowledgement message is used toindicate that the network device rejects forwarding of the positioningassistance data, the positioning server may send the positioningassistance data to the terminal device in unicast mode according to thesolution in the prior art.

Therefore, in this embodiment of this application, even though theforwarding request of the positioning server is not accepted, thepositioning assistance data may be sent to the terminal device inexisting unicast mode, to improve compatibility of the method in thisembodiment of this application.

In an implementation of the first aspect, the positioning assistancedata includes differential satellite positioning assistance data, andbefore the receiving, by a network device, a positioning assistance datamessage sent by a positioning server, the method further includes:receiving, by the network device, a positioning information requestmessage sent by the positioning server, where the positioning requestmessage is used to request to obtain device information of the networkdevice, and the device information includes at least one of thefollowing information: location information of the network device andidentification information of the network device; and sending, by thenetwork device, a positioning information response message to thepositioning server, where the positioning response message carries thedevice information.

In an implementation of the first aspect, the positioning assistancedata message is a Long Term Evolution Positioning Protocol LPPa message.

Optionally, the positioning request message and the positioning responsemessage may also be a Long Term Evolution Positioning Protocol LPPamessage.

Therefore, in this embodiment of this application, the network devicebroadcasts the message to broadcast the positioning assistance data. Inthis way, a problem of low efficiency of transmitting existingcentralized positioning assistance data can be resolved, and a problemin the prior art that a positioning server needs to perform signalingcommunication with each terminal device in a unicast transmissionscenario can be avoided, thereby reducing signaling overheads.

According to a second aspect, a method for transmitting positioningassistance data is provided. The method includes: receiving, by anetwork device, at least one positioning assistance data message sent bya positioning server, where the at least one positioning assistance datamessage is used to carry positioning assistance data; and broadcasting,by the network device to a terminal device, a system message carryingthe positioning assistance data.

Therefore, in this embodiment of this application, the network devicebroadcasts the message to broadcast the positioning assistance data. Inthis way, a problem of low efficiency of transmitting existingcentralized positioning assistance data can be resolved, and a problemin the prior art that a positioning server needs to perform signalingcommunication with each terminal device in a unicast transmissionscenario can be avoided, thereby reducing signaling overheads.

According to a third aspect, a method for transmitting positioningassistance data is provided. The method includes: receiving, by anetwork device, at least one positioning assistance data message sent bya positioning server, where the at least one positioning assistance datamessage is used to carry positioning assistance data; and broadcasting,by the network device to a terminal device, a system message carryingsecond indication information, where the second indication informationis used to instruct the network device to transmit a third resourcelocation for sending the positioning assistance data.

Optionally, in an implementation of the third aspect, the network devicesends the positioning assistance data at the third resource location.

Therefore, in this embodiment of this application, the network devicesends the positioning assistance data to the terminal device by usingtwo steps. The second indication information having a relatively smalldata volume may be added to the system message to reduce a size of thesystem message. In addition, a problem of low efficiency of transmittingexisting centralized positioning assistance data can be resolved, and aproblem in the prior art that a positioning server needs to performsignaling communication with each terminal device in a unicasttransmission scenario can be avoided, thereby reducing signalingoverheads.

According to a fourth aspect, a method for transmitting positioningassistance data is provided. The method includes: obtaining, by apositioning server, positioning assistance data; and sending, by thepositioning server, at least one positioning assistance data message toa network device, where the at least one positioning assistance datamessage is used to carry the positioning assistance data, thepositioning assistance data message is used to trigger the networkdevice to broadcast a system message to a terminal device, the broadcastsystem message carries at least one first parameter, each firstparameter is used by the terminal device to detect first indicationinformation at a first resource location, and the first indicationinformation is used to instruct the network device to send a secondresource location of the positioning assistance data.

Therefore, in this embodiment of this application, the positioningserver sends the positioning assistance data to the network device, andtriggers the network device to broadcast the system message to theterminal device, to broadcast the positioning assistance data. In thisway, a problem of low efficiency of transmitting existing centralizedpositioning assistance data can be resolved, and a problem in the priorart that a positioning server needs to perform signaling communicationwith each terminal device in a unicast transmission scenario can beavoided, thereby reducing signaling overheads.

In an implementation of the fourth aspect, when the positioningassistance data includes at least two pieces of positioning assistancesubdata, that the at least one positioning assistance data message isused to carry the positioning assistance data includes: each positioningassistance data message carries one piece of positioning assistancesubdata.

It should be understood that the fourth aspect corresponds to the firstaspect, the first aspect is performed by the network device, and thefourth aspect may be performed by the positioning server device. Forcorresponding features of the method on a side of the positioningserver, refer to corresponding descriptions of the method on a side ofthe network device in the first aspect. Therefore, for brevity, detailsare properly omitted.

In an implementation of the fourth aspect, before the sending, by thepositioning server, a positioning assistance data message to a networkdevice, the method further includes: sending, by the positioning server,a request message to the network device, where the request message isused to request the network device to forward the positioning assistancedata; and receiving, by the positioning server, a responseacknowledgement message sent by the network device, where the responseacknowledgement message is used to indicate whether the network deviceaccepts forwarding of the positioning assistance data.

In an implementation of the fourth aspect, the positioning assistancedata includes differential satellite positioning assistance data, andbefore the receiving, by a network device, a positioning assistance datamessage sent by a positioning server, the method further includes:receiving, by the network device, a positioning information requestmessage sent by the positioning server, where the positioning requestmessage is used to request to obtain device information of the networkdevice, and the device information includes at least one of thefollowing information: location information of the network device andidentification information of the network device; and sending, by thenetwork device, a positioning information response message to thepositioning server, where the positioning response message carries thedevice information.

In an implementation of the fourth aspect, the positioning assistancedata message is a Long Term Evolution Positioning Protocol (LPPa)message.

Optionally, the positioning request message and the positioning responsemessage may also be a Long Term Evolution Positioning Protocol (LPPa)message.

According to a fifth aspect, a method for transmitting positioningassistance data is provided. The method includes: obtaining, by apositioning server, positioning assistance data; and sending, by thepositioning server, at least one positioning assistance data message toa network device, where the at least one positioning assistance datamessage is used to carry the positioning assistance data, thepositioning assistance data message is used to trigger the networkdevice to broadcast a system message to a terminal device, the systemmessage carries second indication information, the second indicationinformation is used to instruct the network device to transmit a thirdresource location for sending the positioning assistance data, and thethird resource location bears the positioning assistance data sent bythe network device.

Therefore, in this embodiment of this application, the network devicesends the positioning assistance data to the terminal device by usingtwo steps. The second indication information having a relatively smalldata volume may be added to the system message to reduce a size of thesystem message. In addition, a problem of low efficiency of transmittingexisting centralized positioning assistance data can be resolved, and aproblem in the prior art that a positioning server needs to performsignaling communication with each terminal device in a unicasttransmission scenario can be avoided, thereby reducing signalingoverheads.

According to a sixth aspect, a method for transmitting positioningassistance data is provided. The method includes: obtaining, by apositioning server, positioning assistance data; and sending, by thepositioning server, at least one positioning assistance data message toa network device, where the at least one positioning assistance datamessage is used to carry the positioning assistance data, thepositioning assistance data message is used to trigger the networkdevice to broadcast a system message to a terminal device, and thesystem message carries the positioning assistance data.

Therefore, in this embodiment of this application, the network devicebroadcasts the message to broadcast the positioning assistance data. Inthis way, a problem of low efficiency of transmitting existingcentralized positioning assistance data can be resolved, and a problemin the prior art that a positioning server needs to perform signalingcommunication with each terminal device in a unicast transmissionscenario can be avoided, thereby reducing signaling overheads.

According to a seventh aspect, a method for transmitting positioningassistance data is provided. The method includes: receiving, by aterminal device, a system message that is broadcast by a network deviceand that carries at least one first parameter; detecting, by theterminal device, a first indication message at a first resource locationbased on the first parameter, where the first indication information isused to indicate a second resource location at which the network deviceis to send positioning assistance data; and obtaining, by the terminaldevice, the positioning assistance data based on the second resourcelocation indicated by the first indication information.

Optionally, the positioning assistance data includes differentialsatellite positioning assistance data.

Therefore, in this embodiment of this application, the positioningserver sends the positioning assistance data to the network device, andtriggers the network device to broadcast the system message to theterminal device, to broadcast the positioning assistance data. In thisway, a problem of low efficiency of transmitting existing centralizedpositioning assistance data can be resolved, and a problem in the priorart that a positioning server needs to perform signaling communicationwith each terminal device in a unicast transmission scenario can beavoided, thereby reducing signaling overheads.

According to an eighth aspect, a method for transmitting positioningassistance data is provided. The method includes: receiving, by theterminal device, a system message that is broadcast by a network deviceand that carries second indication information, where the secondindication information is used to instruct the network device totransmit a third resource location for sending the positioningassistance data; and obtaining, by the terminal device, the positioningassistance data based on the third resource location indicated by thesecond indication information.

Therefore, in this embodiment of this application, the network devicesends the positioning assistance data to the terminal device by usingtwo steps. The second indication information having a relatively smalldata volume may be added to the system message to reduce a size of thesystem message. In addition, a problem of low efficiency of transmittingexisting centralized positioning assistance data can be resolved, and aproblem in the prior art that a positioning server needs to performsignaling communication with each terminal device in a unicasttransmission scenario can be avoided, thereby reducing signalingoverheads.

According to a ninth aspect, a method for transmitting positioningassistance data is provided. The method includes: receiving, by theterminal device, a system message that is broadcast by a network deviceand that carries positioning assistance data; and obtaining, by theterminal device, the positioning assistance data based on the systeminformation.

Therefore, in this embodiment of this application, the network devicebroadcasts the message to broadcast the positioning assistance data. Inthis way, a problem of low efficiency of transmitting existingcentralized positioning assistance data can be resolved, and a problemin the prior art that a positioning server needs to perform signalingcommunication with each terminal device in a unicast transmissionscenario can be avoided, thereby reducing signaling overheads.

Optionally, in any optional implementation of the first to the ninthaspects, the positioning assistance data may be observed time differenceof arrival (OTDOA) positioning assistance data, correction data,ephemeris data, or real-time kinematic (RTK) data.

The positioning assistance data may be RTK data, ephemeris data, RTKcorrection data or correction data, and other data transmitted by usinga differential signal format (RTCM). The embodiments of this applicationare not limited thereto.

In the embodiments of this application, the positioning assistance datamay be transmitted by using a differential signal format (RTCM). Forexample, after obtaining the positioning assistance data, a referencestation transmits the positioning assistance data to an RTK server byusing the RTCM transmission format.

Optionally, the positioning server may obtain the positioning assistancedata from the RTK positioning server. The positioning server may sendthe positioning assistance data to the network device by using an MME,or may send the positioning assistance data to the network device byusing an LPPa message. The embodiments of this application are notlimited thereto.

It should be understood that the positioning server may further receiveat least one of the following information sent by the RTK positioningserver: an identifier of the network device (for example, a targeteNodeB identifier (Target eNB ID)), a cell identifier (Cell ID) of theterminal device, an area identifier (Area ID) of the terminal device, atransmission procedure identifier (transaction ID)/a service identifier,a quality of service QoS requirement of the RTK data, and a datatransmission rate of the positioning assistance data obtained by the RTKserver. Specifically, the RTK server may send the information to thepositioning server by using an interface message.

It should be understood that the interface message in the embodiments ofthis application may further be used to transmit other information. Thatis, a message transmitted through an interface between the RTK serverand the positioning server is not limited thereto.

It should be noted that usage of the information is not limited in theembodiments of this application. For example, the positioning server maydetermine, based on the information, the network device, a cell in whichthe terminal device is located, the terminal device, or the like. Theembodiments of this application are not limited thereto. Optionally, thepositioning server may obtain the information separately. That is, thepositioning server may obtain only the information, and does not obtainthe positioning assistance data. In this case, the positioning servermay perform positioning analysis based on the obtained information oruse the obtained information for another purpose. This is not limited inthe embodiments of this application.

According to a tenth aspect, a network device is provided. The networkdevice is configured to perform the method according to any possibleimplementation of the first to the third aspects. Specifically, thenetwork device includes a unit configured to perform the foregoingmethod.

According to an eleventh aspect, a positioning server is provided. Thepositioning server is configured to perform the method according to anypossible implementation of the fourth to the sixth aspects.Specifically, the positioning server includes a unit configured toperform the foregoing method.

According to a twelfth aspect, a terminal device is provided. Theterminal device is configured to perform the method according to anypossible implementation of the seventh to the ninth aspects.Specifically, the terminal device includes a unit configured to performthe foregoing method.

According to a thirteenth aspect, a network device is provided. Thenetwork device includes a processor and a memory. The memory isconfigured to store a computer program, and the processor is configuredto perform the computer program stored in the memory, to perform themethod according to any possible implementation of the first to thethird aspects.

According to a fourteenth aspect, a positioning server is provided. Thepositioning server includes a processor and a memory. The memory isconfigured to store a computer program, and the processor is configuredto perform the computer program stored in the memory, to perform themethod according to any possible implementation of the fourth to thesixth aspects.

According to a fifteenth aspect, a terminal device is provided. Theterminal device includes a processor and a memory. The memory isconfigured to store a computer program, and the processor is configuredto perform the computer program stored in the memory, to perform themethod according to any possible implementation of the seventh to theninth aspects.

According to a sixteenth aspect, a computer readable medium is provided,and is configured to store a computer program. The computer programincludes an instruction used to perform the method according to anypossible implementation of the first to the third aspects.

According to a seventeenth aspect, a computer readable medium isprovided, and is configured to store a computer program. The computerprogram includes an instruction used to perform the method according toany possible implementation of the fourth to the sixth aspects.

According to an eighteenth aspect, a computer readable medium isprovided, and is configured to store a computer program. The computerprogram includes an instruction used to perform the method according toany possible implementation of the seventh to the ninth aspects.

According to a nineteenth aspect, a computer program product isprovided. When being executed by a computer, the computer programproduct is configured to implement the method according to any possibleimplementation of the first to the third aspects.

According to a twentieth aspect, a computer program product is provided.When being executed by a computer, the computer program product isconfigured to implement the method according to any possibleimplementation of the fourth to the sixth aspects.

According to a twenty-first aspect, a computer program product isprovided. When being executed by a computer, the computer programproduct is configured to implement the method according to any possibleimplementation of the seventh to the ninth aspects.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a system scenario to which anembodiment of this application can be applied;

FIG. 2 is a schematic diagram of a system scenario to which anembodiment of this application can be applied;

FIG. 3 is a schematic diagram of a scenario in which a terminal devicemeasures positioning data;

FIG. 4 is a flowchart of a method for transmitting positioningassistance data according to an embodiment of this application;

FIG. 5 is a flowchart of a method for transmitting positioningassistance data according to another embodiment of this application;

FIG. 6 is a flowchart of a method for transmitting positioningassistance data according to another embodiment of this application;

FIG. 7 is a flowchart of a method for transmitting positioningassistance data according to another embodiment of this application;

FIG. 8 is a flowchart of a method for transmitting positioningassistance data according to another embodiment of this application;

FIG. 9 is a flowchart of a method for transmitting positioningassistance data according to another embodiment of this application;

FIG. 10 is a flowchart of a method for transmitting positioningassistance data according to another embodiment of this application;

FIG. 11 is a flowchart of a method for transmitting positioningassistance data according to another embodiment of this application;

FIG. 12 is a flowchart of a method for transmitting positioningassistance data according to another embodiment of this application;

FIG. 13 is a schematic block diagram of a network device according to anembodiment of this application;

FIG. 14 is a schematic block diagram of a positioning server accordingto an embodiment of this application; and

FIG. 15 is a schematic block diagram of a terminal device according toan embodiment of this application.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The following clearly describes the technical solutions in theembodiments of this application with reference to the accompanyingdrawings in the embodiments of this application.

The embodiments of this application may be applied to variouscommunications systems. Therefore, the following descriptions are notlimited to a particular communications system. For example, theembodiments of this application may be applied to a Global System forMobile Communications (GSM) system, a Code Division Multiple Access(CDMA) system, a Wideband Code Division Multiple Access (WCDMA) system,a general packet radio service (GPRS), a Long Term Evolution (LTE)system, an LTE frequency division duplex (FDD) system, an LTE timedivision duplex (TDD), a Universal Mobile Telecommunications System(UMTS), an NB-IoT system, and the like.

FIG. 1 is a schematic diagram of a system scenario to which anembodiment of this application can be applied. Network elements includedin the system scenario shown in FIG. 1 may include a terminal device, anetwork device, a positioning server, and a mobility management entity(MME).

In this embodiment of this application, the MME may be a control nodefor processing signaling interaction between the terminal device and acore network. For example, the MME may transfer or forward informationbetween the network device and the positioning server.

In this embodiment of this application, the terminal device is an entityhaving a sending or receiving function, and the terminal device may alsobe referred as to user equipment (UE), an access terminal, a subscriberunit, a subscriber station, a mobile station, a mobile console, a remotestation, a remote terminal, a mobile device, a user terminal, aterminal, a wireless communications device, a user agent, or a userapparatus. The access terminal may be a cellular phone, a cordlessphone, a Session Initiation Protocol (SIP) phone, a wireless local loop(WLL) station, a personal digital assistant (PDA), a handheld devicehaving a wireless communication function, a computing device, anotherprocessing device connected to a wireless modem, an in-vehicle device, awearable device, or a terminal device in a future 5G network.

In this embodiment of this application, the network device is an entityhaving a sending or receiving function, and the network device may be adevice such as a network side device configured to communicate with amobile device. The network side device may be an existing cellular basestation, or may be a cellular base station provided with a satellitereference station. For example, the network device may be a basetransceiver station (BTS) in Global System of Mobile communication (GSM)or Code Division Multiple Access (CDMA); or may be an NB (NodeB, NodeB)in Wideband Code Division Multiple Access (WCDMA); or may be an eNB orevolved NodeB (eNodeB) in Long Term Evolution (LTE), a relay station oran access point, an in-vehicle device, a wearable device, or a networkside device in a future 5G network.

In this embodiment of this application, the positioning server may be apositioning server, for example, an enhanced serving mobile locationcenter (E-SMLC) or an SUPL location platform (SLP), and responsible formanaging coordination and scheduling of all resources required forfinding a location of UE attached to an E-UTRAN. Based on a receivedpositioning measurement estimation value, a final location is computed,and a speed, location information, and the like of the UE are estimated.

FIG. 2 is a schematic diagram of a system scenario to which anembodiment of this application can be applied. Network elements includedin the system scenario shown in FIG. 2 may include a terminal device, anetwork device, a positioning server, a mobility management entity(MME), and a real-time kinematic (RTK) positioning server.

Compared with the scenario in FIG. 1, in the scenario shown in FIG. 2,in the system, the positioning server may communicate with the RTKserver, and the positioning server may obtain positioning assistancedata from the RTK server.

For the network elements in FIG. 2, refer to descriptions of samenetwork elements in FIG. 1. To avoid repetition, details are notdescribed herein again.

Specifically, in the system scenario shown in FIG. 1, when the terminaldevice needs to be positioned, the positioning server receives apositioning request used to request to position the terminal device. Thepositioning request may be sent by the terminal device, the networkdevice, the MME, or another core network or access network device. Afterreceiving the positioning request, the positioning server processes therequest, and sends positioning assistance data to the terminal device.The terminal device performs measurement based on the positioningassistance data, to obtain a positioning measurement estimation value(measurement data). Then, the terminal device reports the positioningmeasurement estimation value to the positioning server. The positioningserver computes a final location of the terminal device based on thereceived positioning measurement estimation value, and can also estimateinformation about, for example, a speed of, the terminal device.

It should be understood that positioning methods that can be applied tothis embodiment of this application include observed time difference ofarrival (OTDOA) positioning, uplink time difference of arrival (UTDOA)positioning, A-GNSS positioning, E-CID positioning, air pressure sensorpositioning, TBS positioning, WLAN positioning, Bluetooth positioning,and the like. The A-GNSS may include a high-precision differential GNSSmethod, for example, differential satellite positioning methods such asRTD (Real-time Differential), RTK (Real-time Kinematic), and network RTK(Network Real-time Kinematic). This embodiment of this application isnot limited thereto.

For example, using the OTDOA as an example, the positioning serverpositions the terminal device based on a reference signal timedifference that is between a neighboring cell and a serving cell andthat is observed by a receiver of the terminal device. Specifically, asshown in FIG. 3, after receiving the positioning assistance data sent bythe positioning server, the terminal device may perform measurementbased on the positioning assistance data, to obtain the positioningmeasurement estimation value. The measurement data may be time pointsthat are of reference signals of the neighboring cell and the servingcell and that are observed by the receiver of the terminal device. Forexample, obtained time points of cells A, B, and C are T₁, T₂, and T₃respectively. Alternatively, the measurement data may be the referencesignal time difference that is between the neighboring cell and theserving cell and that is observed by the receiver of the terminaldevice. Then, the terminal device reports the measurement data to thepositioning server. Further, the positioning server may compute thelocation information, the speed information, or the like of the terminaldevice based on the measurement data. In the methods, the OTDOA-basedlocation estimation method needs to be performed based on a timedifference between at least two pairs of cells.

However, it should be noted that in an existing protocol, a positioningserver needs to provide positioning assistance data to a terminal devicein point-to-point unicast mode. In a scenario in which there are a largequantity of connections or a large quantity of positioning requests,using the solution of transmitting the positioning assistance data inpoint-to-point unicast mode causes low efficiency of transmitting thepositioning assistance data.

In the scenario of FIG. 2, when positioning needs to be performed, theRTK server may obtain positioning assistance data (for example,ephemeris data or correction data) from a reference station, and sendthe positioning assistance data to the positioning server. Then, thepositioning server needs to provide the positioning assistance data forthe terminal device in point-to-point unicast mode, and the terminaldevice may perform positioning based on the positioning assistance data.

It should be understood that the reference station may receive asatellite signal, and may communicate with the RTK server to transmitthe positioning assistance data to the RTK server. The reference stationmay be a base station, for example, a Qianxun reference station oranother reference station. This is not limited in this embodiment ofthis application.

It should be understood that the RTK server in this embodiment of thisapplication may also be referred to as a data center, a control center,a computing center, or a network processing center. The data center, thecontrol center, the computing center, or the network processing centermay be configured to compute correction data through modeling. Thisembodiment of this application is not limited thereto.

The problem in FIG. 1 also exists in the scenario in FIG. 2. That is, ina scenario in which there are a large quantity of connections or a largequantity of positioning requests, using the solution of transmitting thepositioning assistance data in point-to-point unicast mode causes lowefficiency of transmitting the positioning assistance data.

In view of this problem, the embodiments of this application skillfullyprovide a solution in which the network device broadcasts and forwardsthe positioning assistance data, so as to resolve a problem of lowefficiency of transmitting existing centralized positioning assistancedata.

For convenience of understanding and description, by way of example butnot limitation, a process and actions of performing a method fortransmitting positioning assistance data in this application in thecommunications system are described below.

It should be understood that positioning methods that can be applied tothe embodiments of this application include OTDOA positioning, UTDOApositioning, A-GNSS positioning, E-CID positioning, air pressure sensorpositioning, TBS positioning, WLAN positioning, Bluetooth positioning,and the like. The A-GNSS may include a high-precision differential GNSSmethod, for example, differential satellite positioning methods such asRTD (Real-time Differential), RTK (Real-time Kinematic), and network RTK(Network Real-time Kinematic). The OTDOA is used as an example fordescription in the following embodiments, but the embodiments of thisapplication are not limited thereto. When another positioning method isused, corresponding interaction signaling may change correspondingly.

It should be understood that unless otherwise specially stated, a typeof interaction signaling between the network device and the positioningserver in the embodiments of this application may be an LPPa message. Toavoid repetition, details are not further described below.

It should further be understood that same reference numerals in theaccompanying drawings in the embodiments of this application representsame content. To avoid repetition, details are properly omitted belowafter descriptions of a same reference numeral are provided. Forspecific content of a reference numeral that appears again, refer toprevious corresponding descriptions of the reference numeral, anddetails are not further described below.

It should be understood that the positioning assistance data in theembodiments of this application may include a physical cell identifier(PCI), an evolved universal terrestrial radio access network cell globalidentifier (ECGI), an evolved universal terrestrial radio accessabsolute radio frequency channel number (EARFCN), a positioningreference signal bandwidth, a cyclic prefix length, a cell-dedicatedreference signal port quantity, a positioning reference signal subframeconfiguration (a period/an offset/a quantity of consecutive subframes),a positioning reference signal silence configuration, a cyclic prefixlength, and a cell-dedicated reference signal port quantity of areference cell; a physical cell identifier (PCI), an evolved universalterrestrial radio access network cell global identifier (ECGI), anevolved universal terrestrial radio access absolute radio frequencychannel number (EARFCN), a positioning reference signal bandwidth, apositioning reference signal subframe configuration (a period/anoffset/a quantity of consecutive subframes), a positioning referencesignal silence configuration, a cyclic prefix length, a cell-dedicatedreference signal port quantity, a subframe quantity offset, apositioning reference signal subframe offset, a search window, anexpected reference signal time difference, expected reference signaltime difference uncertainty, and the like of a neighboring cell;information related to a coverage level, for example, a quantity ofcells needing to be measured; and differential satellite positioningassistance data based on a location of a base station, where thedifferential satellite positioning assistance data includes pseudorangedifferential, positional differential, carrier phase differential, andthe like. The embodiments of this application are not limited thereto.

FIG. 4 is a schematic flowchart of a method for transmitting positioningassistance data according to an embodiment of this application. Themethod shown in FIG. 4 may be applied to the foregoing variouscommunications systems. Specifically, the method 300 shown in FIG. 4includes the following steps.

310. A positioning server sends at least one positioning assistance datamessage to a network device.

Specifically, the at least one positioning assistance data message isused to carry positioning assistance data.

For example, after obtaining a positioning request, the positioningserver may send, based on a size of a positioning assistance datapacket, the obtained positioning assistance data to the network deviceby using one or more positioning assistance data messages. Thepositioning server may obtain the positioning assistance data in amanner specified in an existing standard. For example, as shown in FIG.4, before step 310, the method may further include the following steps.

3101. The positioning server sends an OTDOA information request messageto the network device, where the OTDOA information request message isused to request to obtain positioning assistance data corresponding tothe network device needing to perform OTDOA positioning.

3102. The network device sends an OTDOA response message to thepositioning server, where the OTDOA response message carries thepositioning assistance data corresponding to the network device.

It should be understood that step 3101 and step 3102 are described onlyby using an OTDOA positioning method as an example. When the positioningmethod is another positioning method, the OTDOA request message and theOTDOA response message in step 3101 and step 3102 may changecorrespondingly.

For example, when a UTDOA positioning method is merely used as anexample, the OTDOA request message and the OTDOA response message instep 3101 and step 3102 are correspondingly changed to a UTDOA requestmessage and a UTDOA response message.

It should be understood that in step 3101, the positioning server mayalternatively send the OTDOA information request message to a networkdevice in a neighboring cell of a cell in which the network device islocated, to request to obtain positioning assistance data correspondingto the network device in the neighboring cell. Then, the positioningserver may summarize positioning assistance data corresponding to aplurality of network devices to form the positioning assistance datasent by the positioning server in step 310 in FIG. 4. Specifically, fora specific process of obtaining, by the positioning server, thepositioning assistance data needing to be sent, refer to a specificprocess in an existing standard. For brevity, details are not describedherein. After obtaining the positioning assistance data, the positioningserver sends the positioning assistance data to the network device byusing the at least one positioning assistance data message.

For example, when a positioning assistance data packet is relativelysmall, the positioning server may send one positioning assistance datamessage to the network device, where the positioning assistance datamessage carries the positioning assistance data.

Therefore, in this embodiment of this application, the positioningassistance data can be sent by using only one positioning assistancedata message, thereby reducing signaling overheads and providing systemperformance.

For another example, when a positioning assistance data packet isrelatively large, the positioning server may send N positioningassistance data messages to the network device, where N is an integergreater than or equal to 2, and the N positioning assistance datamessages are used to carry the positioning assistance data.

Specifically, the positioning assistance data may include N pieces ofpositioning assistance subdata, and the positioning assistance datamessage includes N positioning assistance subdata messages.

The receiving, by a network device, a positioning assistance datamessage sent by a positioning server includes: receiving, by the networkdevice, the N positioning assistance subdata messages sent by thepositioning server, where each of the N positioning assistance subdatamessages carries one of the N pieces of positioning assistance subdata.

It should be understood that in this embodiment of this application,data volumes of the N pieces of positioning assistance subdata may beapproximately equal or may not be equal. The positioning server maydetermine an amount of each piece of positioning assistance subdatadepending on an actual situation. This is not limited in this embodimentof this application.

Therefore, in this embodiment of this application, when the positioningassistance data is relatively large, the positioning assistance data maybe sent by using a plurality of positioning assistance data messages, toavoid generation of an excessively large message. In addition, whentransmission of a positioning assistance data message fails, only thepositioning assistance data message of which transmission fails needs tobe retransmitted, thereby reducing a quantity of data retransmissionsand improving system performance.

320. The network device broadcasts a system message to a terminaldevice.

Specifically, the system message is used by the terminal device toobtain the positioning assistance data. The system message may be a MIB,a SIB, a positioning-dedicated SIB, or the like. This embodiment of thisapplication is not limited thereto.

Therefore, in this embodiment of this application, the network devicebroadcasts the system message to broadcast the positioning assistancedata. In this way, a problem of low efficiency of transmittingpositioning assistance data in the prior art can be resolved, and aproblem in the prior art that a positioning server needs to performsignaling communication with each terminal device in a unicasttransmission scenario can be avoided, thereby reducing signalingoverheads.

In addition, the positioning server in this embodiment of thisapplication can send the positioning assistance data to the networkdevice with no need to request the network device, thereby reducingsignaling overheads.

Optionally, in another embodiment, as shown in FIG. 5, before step 310,the method in this embodiment of this application may further includethe following steps.

311. The positioning server sends a request message to the networkdevice, where the request message is used to request the network deviceto forward the positioning assistance data.

312. The network device sends a response acknowledgement message to thepositioning server, where the response acknowledgement message is usedto indicate whether the network device accepts forwarding of thepositioning assistance data.

Step 310 is performed only when the response acknowledgement message isused to indicate that the network device accepts forwarding of thepositioning assistance data.

Therefore, in this embodiment of this application, the positioningserver can send the positioning assistance data to the network deviceonly when the request is accepted. Compared with a case in which thereis no request, a response of the network device can be received when therequest is not accepted, thereby avoiding unnecessary transmission andavoiding a waste of resources.

Alternatively, when the response acknowledgement message is used toindicate that the network device rejects forwarding of the positioningassistance data, the positioning server may send the positioningassistance data to the terminal device in unicast mode according to thesolution in the prior art.

Therefore, in this embodiment of this application, even though theforwarding request of the positioning server is not accepted, thepositioning assistance data may be sent to the terminal device inexisting unicast mode, to improve compatibility of the method in thisembodiment of this application.

It should be noted that in FIG. 5, the positioning server sends aseparate message that carries the request message used to request thenetwork device to forward the positioning assistance data.

Alternatively, in another embodiment, as shown in FIG. 6, based on FIG.4, the request message is carried in one of the at least one positioningassistance data message. Likewise, the request message is used torequest the network device to forward the positioning assistance data.

Optionally, as shown in FIG. 6, the method may further include thefollowing steps.

323. The network device sends a response acknowledgement message to thepositioning server, where the response acknowledgement message is usedto indicate whether the network device accepts forwarding of thepositioning assistance data.

Step 310 is performed only when the response acknowledgement message isused to indicate that the network device accepts forwarding of thepositioning assistance data.

Alternatively, when the response acknowledgement message is used toindicate that the network device rejects forwarding of the positioningassistance data, the positioning server may send the positioningassistance data to the terminal device in unicast mode according to thesolution in the prior art.

It should be noted that when there are two or more pieces of positioningassistance data, the present disclosure can be implemented provided thatstep 323 is performed after the positioning assistance data messagecarrying the positioning assistance request message is sent and beforestep 320 is performed. Step 323 may be relatively flexibly performed inthis embodiment of this application. For example, step 323 may beperformed between sending of two positioning assistance data messages,or may be performed after all positioning assistance data messages aresent.

It should be noted that, that the positioning server obtains thepositioning assistance data according to the existing solution isdescribed above. That is, the positioning server obtains the positioningassistance data by requesting the network device.

Alternatively, in this embodiment of this application, the positioningassistance data may be obtained in another manner. For example, when thepositioning assistance data includes differential satellite positioningassistance data, step 3101 and step 3102 in FIG. 4 to FIG. 6 may bereplaced with the following steps.

3103. The positioning server sends a positioning information requestmessage to the network device.

For example, the positioning information request message may be anA-GNSS information request message. The positioning information requestmessage is used to request to obtain device information of the networkdevice. The device information may include at least one of the followinginformation: location information of the network device andidentification information of the network device.

3104. The network device sends a positioning information responsemessage to the positioning server.

Specifically, the positioning information response message carries thedevice information. In this way, the positioning server determines thepositioning assistance data based on the obtained device information.

For example, when the positioning assistance data is differentialsatellite positioning assistance data, step 3101 and step 3102 in FIG. 4may be replaced with step 3103 and step 3104 to form an embodiment ofFIG. 7. Specific processing processes of other steps are the same, and adifference lies only in that content of the positioning assistance datais different. Optionally, when the positioning assistance data isdifferential satellite positioning assistance data, the embodiments ofFIG. 5 and FIG. 6 may form corresponding embodiments by replacing step3101 and step 3102 with step 3103 and step 3104. For brevity, no furtherfigures are provided for expression herein.

It should be understood that in this embodiment of this application, anA-GNSS (Assisted Global Navigation Satellite System) informationresponse message includes location information of a base station and anidentity of the base station (whether the base station is a satellitereference station). Subsequent messages and procedures are the same asthose in the foregoing embodiment. A GNSS (Global Navigation SatelliteSystem) includes a GPS (Global Positioning System), a modern GPS, aGalileo (Galileo), a GLONASS (Global Navigation Satellite System), anSBAS (Space Based Augmentation System), a QZSS (Quasi Zenith SatelliteSystem), a BDS (BeiDou Navigation Satellite System), and the like.Different GNSSs (for example, the GPS and the Galileo) may independentlyor jointly be applied to assisted positioning.

It should be understood that the positioning request message in step3103 in this embodiment of this application may carry a list of datathat needs to be requested, and the network device may feed backcorresponding data based on the list. Alternatively, the positioningrequest message in step 3104 may not carry a list of data that needs tobe requested. After obtaining the request message, the network devicemay feed back corresponding data according to a predefined list (rule).This is not limited in this embodiment of this application.

All of the foregoing various embodiments described in FIG. 4 and FIG. 7can be applied to the system scenarios shown in FIG. 1 and FIG. 2. Adifference lies in that manners of obtaining the positioning assistancedata are different. When the embodiments are applied to the scenario inFIG. 1, the positioning server may obtain the positioning assistancedata in the manner in step 3101 and step 3102. When the embodiments areapplied to the scenario in FIG. 2, the positioning server may obtain thepositioning assistance data from an RTK positioning server.Specifically, during positioning, the RTK positioning server may obtainthe positioning assistance data, for example, obtain the positioningassistance data from a reference station. Then, the RTK positioningserver sends the positioning assistance data to the positioning server.

Specifically, as shown in FIG. 8, before step 310, the method mayfurther include the following step.

3105. The RTK positioning server sends the positioning assistance datato the positioning server.

For example, after obtaining the positioning assistance data from thereference station, the RTK positioning server sends the positioningassistance data to the positioning server. The reference station may bea base station, for example, a Qianxun reference station or anotherreference station. This is not limited in this embodiment of thisapplication.

The positioning assistance data may be RTK data, ephemeris data, RTDdata or correction data, and other data transmitted by using adifferential signal format (RTCM). This embodiment of this applicationis not limited thereto.

It should be understood that the positioning server may further receiveat least one of the following information sent by the RTK positioningserver: an identifier of the network device (for example, a targeteNodeB identifier (Target eNB ID)), a cell identifier (Cell ID) of theterminal device, an area identifier (Area ID) of the terminal device, atransmission procedure identifier (transaction ID)/a service identifier,a quality of service (QoS) requirement of the RTK data, and a datatransmission rate of the positioning assistance data obtained by the RTKserver. Specifically, the RTK server may send the information to thepositioning server by using an interface message.

In this embodiment of this application, the positioning assistance datamay be transmitted by using a differential signal format (RadioTechnical Commission for Maritime services, RTCM). For example, afterobtaining the positioning assistance data, the reference stationtransmits the positioning assistance data to the RTK server by using theRTCM transmission format.

It should be understood that in the embodiments of this application, instep 310, only a situation in which the positioning server sends thepositioning assistance data to the network device by using the at leastone positioning assistance data message is shown. However, theembodiments of this application are not limited thereto. Alternatively,in the embodiments of this application, the positioning server may sendthe positioning assistance data to the network device by using an MME,where the MME sends the data to the network device; or may send thepositioning assistance data to the network device by using an LPPamessage.

It should be noted that in the embodiments of this application, for step320 in the embodiments of FIG. 4 to FIG. 8, the network device mayexplicitly or implicitly transmit the positioning assistance data byusing the system message. Specifically, in an explicit transmissioncase, the system message may carry the positioning assistance data. Inan implicit case, the system message may carry first indicationinformation or parameter information to indicate a resource bearing thepositioning assistance data. An interaction process between the networkdevice and the terminal device is described in detail below for thesecases separately with reference to FIG. 9 to FIG. 12.

Specifically, as shown in FIG. 9, the system message in step 320 carriesthe positioning assistance data.

The system message may be a MIB, a SIB, or a positioning-dedicated SIBin an existing system. The MIB and the SIB may be system messageresources in one of the foregoing plurality of network systems to whichthis embodiment of this application can be applied.

Therefore, in this embodiment of this application, the network devicebroadcasts the message to broadcast the positioning assistance data. Inthis way, a problem of low efficiency of transmitting existingcentralized positioning assistance data can be resolved, and a problemin the prior art that a positioning server needs to perform signalingcommunication with each terminal device in a unicast transmissionscenario can be avoided, thereby reducing signaling overheads.

In the foregoing embodiment, the positioning server may send thepositioning assistance data to the network device (the base station) byusing an LPPa protocol between the positioning server and the networkdevice. Alternatively, the positioning server may first send thepositioning assistance data to a core network device, for example, anMME, and then the core network device sends the positioning assistancedata to the network device.

In another embodiment, when the positioning server and the RTK serverare integrated as one server, the positioning server may directly obtainthe positioning assistance data from the reference station, and send thepositioning assistance data to the network device. A sending manner isthe same as that in the foregoing descriptions, and details are notdescribed herein again.

Alternatively, as shown in FIG. 10, the system message in step 320carries second indication information.

For example, the second indication information may be used to instructthe network device to transmit a third resource location for sending thepositioning assistance data.

For example, the second indication information may be schedulinginformation. The scheduling information may include the third resourcelocation, that is, a frequency-domain resource location of a thirdresource, a scheduling delay, a period, a starting subframe location, anoffset, an MCS, a quantity of repetitions, and the like. This embodimentof this application is not limited thereto.

When the system message carries the second indication information, afterstep 320 in the embodiments of FIG. 4 to FIG. 7, the method may furtherinclude the following step.

321. The terminal device receives the positioning assistance data sentby the network device at the third resource location.

The third resource location, for example, may be a location of a PDSCHresource. The PDSCH may be a PDSCH resource in one of the foregoingplurality of network systems to which this embodiment of thisapplication can be applied.

Therefore, in this embodiment of this application, the network devicesends the positioning assistance data to the terminal device by usingtwo steps. The second indication information having a relatively smalldata volume may be added to the system message to reduce a size of thesystem message. In addition, a problem of low efficiency of transmittingexisting centralized positioning assistance data can be resolved, and aproblem in the prior art that a positioning server needs to performsignaling communication with each terminal device in a unicasttransmission scenario can be avoided, thereby reducing signalingoverheads.

Alternatively, as shown in FIG. ii, the system message in step 320carries at least one first parameter.

For example, the first parameter is used by the terminal device todetect first indication information at a first resource location, andthe first indication information is used to indicate a second resourcelocation at which the network device is to send the positioningassistance data.

Specifically, the first parameter may be a positioning RNTI, the firstresource location may be a location of a PDCCH resource, the firstindication information may be DCI borne on the PDCCH, and the secondresource location may be a location of a PDSCH resource. The PDCCH maybe a PDCCH resource in one of the foregoing plurality of network systemsto which this embodiment of this application can be applied. The PDSCHmay be a PDSCH resource in one of the foregoing plurality of networksystems to which this embodiment of this application can be applied.Specifically, the RNTI may be an RNTI allocated by the network devicefor RTK, for example, an RTK-RNTI, or may be a predefined RNTI for RTKpositioning. Alternatively, the RNTI may be allocated or predefinedaccording to different positioning methods.

Correspondingly, when the system message carries the first parameter,after step 320 in the embodiments of FIG. 4 to FIG. 7, the method mayfurther include the following steps.

322. The network device sends the first indication information at thefirst resource location.

Correspondingly, the terminal device receives the first indicationinformation sent by the network device at the first resource location.

323. The network device sends the positioning assistance data at thesecond resource location.

Correspondingly, the terminal device receives the positioning assistancedata sent by the network device at the second resource location.

Therefore, in this embodiment of this application, the network devicesends the positioning assistance data to the terminal device by usingthree steps. First parameter information having a relatively small datavolume may be added to the system message to reduce a size of the systemmessage. In addition, the first indication information may be detectedon a predefined resource by using the first parameter, to reducesignaling overheads on a second resource. In addition, a problem of lowefficiency of transmitting existing centralized positioning assistancedata can be resolved, and a problem in the prior art that a positioningserver needs to perform signaling communication with each terminaldevice in a unicast transmission scenario can be avoided, therebyreducing signaling overheads.

It should be noted that the at least one first parameter in thisembodiment of this application may include one parameter or may includea plurality of parameters. For example, the first parameter may includea plurality of (groups of) positioning RNTIs, and each (group of)positioning RNTI corresponds to one positioning method or one mode ofone positioning method. For example, a positioning RNTI 1 corresponds toan OTDOA method, and a positioning RNTI 2 corresponds to an A-GNSSmethod.

When the first parameter in this embodiment of this application includesone (group of) positioning RNTI, the terminal completes subsequentreceiving by using the (group of) obtained positioning RNTI. The (groupof) positioning RNTI corresponds to one positioning method, for example,an OTDOA cellular positioning method or GPS satellite positioning.

When the first parameter in this embodiment of this application includestwo (groups of) positioning RNTIs, the terminal completes subsequentreceiving by using the obtained two (groups of) different positioningRNTIs. The two (groups of) different positioning RNTIs correspond to twodifferent positioning methods, for example, OTDOA and GPS satellitepositioning.

When the first parameter in this embodiment of this application includestwo (groups of) positioning RNTIs, the terminal completes subsequentreceiving by using the obtained two (groups of) different positioningRNTIs. The two (groups of) different positioning RNTIs correspond to twodifferent modes of one positioning method, for example, GPS satellitepositioning and BeiDou satellite positioning.

When the first parameter in this embodiment of this application includesthree (groups of) positioning RNTIs, the terminal completes subsequentreceiving by using the obtained three (groups of) different positioningRNTIs. The three (groups of) different positioning RNTIs correspond totwo positioning methods and two different modes of one of the twopositioning methods, for example, OTDOA cellular positioning, GPSsatellite positioning, and BeiDou satellite positioning.

Specifically, each positioning RNTI corresponds to one PDCCH resource,and DCI borne on the PDCCH resource indicates a PDSCH resource bearing acorresponding positioning assistance data. Specifically, the PDSCH bearsMTCH information. That is, a simplified multicast mode is used. Noscheduling is performed on an MCCH, and a PDCCH listened to by UEschedules time frequency resources on an MTCH. The positioningassistance data (which may include OTDOA positioning assistance data,for example, a measurement configuration, RTK data, correction data, orthe like) is transmitted by using the MTCH. Herein, the grouping may beperformed according to different positioning methods, different modescorresponding to a positioning method, or a combination thereof. Thisembodiment of this application is not limited thereto.

Alternatively, as shown in FIG. 12, the system message in step 320carries third indication information.

For example, the third indication information is used to instruct theterminal device to detect fourth indication information on a fourthresource, and the fourth indication information is used to indicate afifth resource location of the positioning assistance data.

For example, the third indication information may be schedulinginformation. The scheduling information may include a fourth resourcelocation. That is, a fourth resource may include at least one of thefollowing information: a frequency-domain resource location, ascheduling delay, a period, a starting subframe location, an offset, anMCS, a quantity of repetitions, and the like. The fourth indicationinformation may be scheduling information. The scheduling informationmay include the fifth resource location. That is, a fifth resource mayinclude at least one of the following information: a frequency-domainresource location, a scheduling delay, a period, a starting subframelocation, an offset, an MCS, a quantity of repetitions, and the like.This embodiment of this application is not limited thereto.

Specifically, the third indication information is used to indicate alocation of a first PDCCH resource. DCI on the first PDCCH resourceinstructs the terminal device to detect the fourth indicationinformation on the fourth resource. For example, the fourth resource isa first PDSCH resource, and the fourth indication information is MCCHinformation.

The fourth indication information may indicate a location of a secondPDCCH resource. DCI on the second PDCCH resource indicates a location ofthe fifth resource bearing the positioning assistance data. For example,the fifth resource is a second PDSCH resource, and the positioningassistance data may be borne on an MTCH traffic channel borne on thesecond PDSCH resource.

Correspondingly, when the system message carries the third indicationinformation, after step 320 in the embodiments of FIG. 4 to FIG. 8, themethod may further include the following steps.

324. The network device sends the fourth indication information on thefourth resource.

325. Send the positioning assistance data at the fifth resourcelocation.

Specifically, the terminal device obtains the third indicationinformation based on the system message.

The terminal device detects the fourth indication information on thefourth resource based on the third indication information.

The terminal device obtains the positioning assistance data on the fifthresource based on the fourth indication information.

For example, the terminal device may descramble a PDCCH by using thefirst parameter (for example, the RTK-RNTI) added by the network deviceto the system message, to obtain the fourth resource location, andobtain the fourth indication information (for example, the MCCHinformation) at the fourth resource location, and further, to detect thefifth resource based on the fourth indication information to obtain thepositioning assistance data.

Therefore, in this embodiment of this application, the network devicesends the positioning assistance data to the terminal device by using aplurality of steps. The third indication information having a relativelysmall data volume may be added to the system message to resolve aproblem that the positioning assistance data cannot be transmitted at atime due to a limited size of the system message. In addition, anexisting problem of low efficiency of transmitting positioningassistance data can be resolved, and a problem in the prior art that apositioning server needs to perform signaling communication with eachterminal device in a unicast transmission scenario can be avoided,thereby reducing signaling overheads.

The method for transmitting positioning assistance data in theembodiments of this application are described in detail above withreference to FIG. 1 to FIG. 12. It should be noted that the examples inFIG. 1 to FIG. 12 are merely intended to help a person skilled in theart understand the embodiments of this application, rather than limitthe embodiments of this application to exemplified specific values orspecific scenarios. Apparently, a person skilled in the art may makevarious equivalent modifications or changes based on the examples inFIG. 1 to FIG. 12. Such modifications or changes shall also fall withinthe range of the embodiments of this application.

It should be understood that sequence numbers of the foregoing processesdo not indicate an execution sequence, and an execution sequence ofprocesses shall be determined based on functions and internal logicthereof, and shall constitute no limitation on an implementation processof the embodiments of this application.

In the following descriptions, the network device in the embodiments ofthis application is described with reference to FIG. 13, the positioningserver in the embodiments of this application is described withreference to FIG. 14, and the terminal device is described withreference to FIG. 15.

FIG. 13 is a schematic block diagram of a network device 1000 accordingto an embodiment of this application. Specifically, as shown in FIG. 13,the network device 1000 includes a processing unit 1010, a receivingunit 1020, and a sending unit 1030. The processing unit 1010 isconnected to the receiving unit 1020 and the sending unit 1030. Itshould be understood that the processing unit 1010 may be a processor.The processor may be a central processing unit (CPU). The processor mayalternatively be another general-purpose processor, a digital signalprocessor (DSP), an application-specific integrated circuit (ASIC), afield programmable gate array (FPGA) or another programmable logicdevice, discrete gate or transistor logic device, or discrete hardwarecomponent, or the like. The general-purpose processor may be amicroprocessor or the processor may be any conventional processor, orthe like.

Optionally, the network device 1000 further includes a memory. Thememory is connected to the processor 1010. The memory may be configuredto store an instruction. The processor 1010 is configured to execute theinstruction stored in the memory, to control the sending unit 1030 tosend a signal or information, and to control the receiving unit 1020 toreceive a signal or information.

Specifically, the receiving unit 1020 is configured to receive apositioning assistance data message sent by a positioning server, wherethe positioning assistance data message is used to carry positioningassistance data.

The sending unit 1030 is configured to broadcast a system message to aterminal device, where the system message is used by the terminal deviceto obtain the positioning assistance data.

Therefore, in this embodiment of this application, the network devicebroadcasts the system message to broadcast the positioning assistancedata. In this way, a problem of low efficiency of transmittingpositioning assistance data in the prior art can be resolved, and aproblem in the prior art that a positioning server needs to performsignaling communication with each terminal device in a unicasttransmission scenario can be avoided, thereby reducing signalingoverheads.

Optionally, in another embodiment, the sending unit is specificallyconfigured to broadcast, to the terminal device, the system messagecarrying the positioning assistance data.

Optionally, in another embodiment, the sending unit is specificallyconfigured to broadcast, to the terminal device, a system messagecarrying second indication information, where the second indicationinformation is used to instruct the network device to transmit a thirdresource location for sending the positioning assistance data.

Optionally, in another embodiment, the sending unit is furtherconfigured to send the positioning assistance data at the third resourcelocation.

Optionally, in another embodiment, the receiving unit 1020 isspecifically configured to receive at least one positioning assistancedata message sent by a positioning server, where the positioningassistance data message is used to carry positioning assistance data.

The sending unit 1030 is configured to broadcast, to the terminaldevice, a system message carrying at least one first parameter, whereeach first parameter is used by the terminal device to detect firstindication information at a first resource location, and the firstindication information is used to indicate a second resource location atwhich the network device is to send the positioning assistance datareceived by the receiving unit 1020.

Therefore, in this embodiment of this application, the network devicebroadcasts the message to broadcast the positioning assistance data. Inthis way, a problem of low efficiency of transmitting existingcentralized positioning assistance data can be resolved, and a problemin the prior art that a positioning server needs to perform signalingcommunication with each terminal device in a unicast transmissionscenario can be avoided, thereby reducing signaling overheads.

Optionally, in another embodiment, the sending unit is furtherconfigured to send the first indication information at the firstresource location, and send, at the second resource location, thepositioning assistance data received by the receiving unit.

Optionally, in another embodiment, when the positioning assistance dataincludes at least two pieces of positioning assistance subdata, that theat least one positioning assistance data message received by thereceiving unit is used to carry positioning assistance data includes:each positioning assistance data message carries one piece ofpositioning assistance subdata.

Optionally, in another embodiment, the receiving unit is furtherconfigured to receive a positioning information request message sent bythe positioning server, where the positioning request message is used torequest to obtain device information of the network device, and thedevice information includes at least one of the following information:location information of the network device and identificationinformation of the network device.

The sending unit is further configured to send a positioning informationresponse message to the positioning server, where the positioningresponse message carries the device information.

Optionally, in another embodiment, the positioning assistance data isephemeris data, real-time kinematic (RTK) data, or correction data.

Optionally, in another embodiment, the positioning assistance datamessage is a Long Term Evolution Positioning Protocol A (LPPa) messageor an RTCM message.

It should be understood that the network device 1000 shown in FIG. 13can implement each process related to the network device in the methodembodiments of FIG. 4 to FIG. 12. Operations and/or functions of variousmodules in the network device 1000 are intended to implementcorresponding procedures in the method embodiments of FIG. 4 to FIG. 12.For details, refer to the descriptions in the method embodiments. Toavoid repetition, details are properly omitted herein.

Therefore, in this embodiment of this application, the network devicebroadcasts the message to broadcast the positioning assistance data. Inthis way, a problem of low efficiency of transmitting existingcentralized positioning assistance data can be resolved, and a problemin the prior art that a positioning server needs to perform signalingcommunication with each terminal device in a unicast transmissionscenario can be avoided, thereby reducing signaling overheads.

FIG. 14 is a schematic block diagram of a positioning server 1100according to an embodiment of this application. Specifically, as shownin FIG. 14, the positioning server 1100 includes a processing unit 1110,a receiving unit 1120, and a sending unit 1130. The processing unit 1110is connected to both the receiving unit 1120 and the sending unit 1130.It should be understood that the processing unit 1110 may be aprocessor. The processor may be a central processing unit (CPU). Theprocessor may alternatively be another general-purpose processor, adigital signal processor (DSP), an application-specific integratedcircuit (ASIC), a field programmable gate array (FPGA) or anotherprogrammable logic device, discrete gate or transistor logic device, ordiscrete hardware component, or the like. The general-purpose processormay be a microprocessor or the processor may be any conventionalprocessor, or the like.

Optionally, the positioning server 1100 further includes a memory. Thememory is connected to the processor 1110. The memory may be configuredto store an instruction. The processor 1110 is configured to execute theinstruction stored in the memory, to control the sending unit 1130 tosend a signal or information, and to control the receiving unit 1120 toreceive a signal or information.

Specifically, the receiving unit 1120 is configured to obtainpositioning assistance data.

The sending unit 1130 is configured to send at least one positioningassistance data message to a network device, where the at least onepositioning assistance data message carries the positioning assistancedata obtained by the receiving unit 1120, the positioning assistancedata message is used to trigger the network device to broadcast a systemmessage to a terminal device, and the system message is used by theterminal device to obtain the positioning assistance data.

Therefore, in this embodiment of this application, the positioningserver sends the positioning assistance data to the network device, andtriggers the network device to broadcast the system message to theterminal device, to broadcast the positioning assistance data. In thisway, a problem of low efficiency of transmitting existing centralizedpositioning assistance data can be resolved, and a problem in the priorart that a positioning server needs to perform signaling communicationwith each terminal device in a unicast transmission scenario can beavoided, thereby reducing signaling overheads.

Optionally, in another embodiment, when the positioning assistance dataincludes at least two pieces of positioning assistance subdata, that theat least one positioning assistance data message sent by the sendingunit 1130 is used to carry positioning assistance data includes: eachpositioning assistance data message carries one piece of positioningassistance subdata.

Optionally, in another embodiment, the positioning assistance dataincludes differential satellite positioning assistance data.

The receiving unit 1120 is further configured to receive a positioninginformation request message sent by the positioning server, where thepositioning request message is used to request to obtain deviceinformation of the network device, and the device information includesat least one of the following information: location information of thenetwork device and identification information of the network device.

The sending unit 1130 is further configured to send a positioninginformation response message to the positioning server, where thepositioning response message carries the device information.

The receiving unit is specifically configured to obtain the positioningassistance data based on the device information.

Optionally, in another embodiment, the positioning assistance data isephemeris data, real-time kinematic (RTK) data, or correction data.

Optionally, in another embodiment, the receiving unit is specificallyconfigured to receive the positioning assistance data sent by an RTKpositioning server.

Optionally, in another embodiment, the positioning assistance datamessage is a Long Term Evolution Positioning Protocol A (LPPa) messageor an RTCM message.

Optionally, in another embodiment, the receiving unit is furtherconfigured to receive at least one of the following information sent bythe RTK positioning server: an identifier of the network device, a cellidentifier of the terminal device, an area identifier of the terminaldevice, a transmission procedure identifier/a service identifier, aquality of service (QoS) requirement of the RTK data, and a datatransmission rate of the positioning assistance data obtained by the RTKserver.

It should be understood that the positioning server 1100 shown in FIG.14 can implement each process related to the positioning server in themethod embodiments of FIG. 4 to FIG. 12. Operations and/or functions ofvarious modules in the positioning server 1100 are intended to implementcorresponding procedures in the method embodiments of FIG. 4 to FIG. 12.For details, refer to the descriptions in the method embodiments. Toavoid repetition, details are properly omitted herein.

Therefore, in this embodiment of this application, the positioningserver sends the positioning assistance data to the network device, andtriggers the network device to broadcast the system message to theterminal device, to broadcast the positioning assistance data. In thisway, a problem of low efficiency of transmitting existing centralizedpositioning assistance data can be resolved, and a problem in the priorart that a positioning server needs to perform signaling communicationwith each terminal device in a unicast transmission scenario can beavoided, thereby reducing signaling overheads.

FIG. 15 is a schematic block diagram of a terminal device 1200 accordingto an embodiment of this application. Specifically, as shown in FIG. 15,the positioning server 1200 includes a processing unit 1210 and areceiving unit 1220. The processing unit 1210 is connected to thereceiving unit 1220. It should be understood that the processing unit1210 may be a processor. The processor may be a central processing unit(CPU). The processor may alternatively be another general-purposeprocessor, a digital signal processor (DSP), an application-specificintegrated circuit (ASIC), a field programmable gate array (FPGA) oranother programmable logic device, discrete gate or transistor logicdevice, or discrete hardware component, or the like. The general-purposeprocessor may be a microprocessor or the processor may be anyconventional processor, or the like.

Optionally, the terminal device 1200 further includes a memory. Thememory is connected to the processor 1210. The memory may be configuredto store an instruction. The processor 1210 is configured to execute theinstruction stored in the memory, to control the receiving unit 1220 toreceive a signal or information.

Specifically, the receiving unit 1220 is configured to receive a systemmessage broadcast by a network device.

The processing unit 1210 is configured to obtain positioning assistancedata based on the system message.

Therefore, in this embodiment of this application, the terminal devicereceives the system message broadcast by the network device, and obtainsthe positioning assistance data based on the system message. In thisway, a problem of low efficiency of transmitting existing centralizedpositioning assistance data can be resolved, and a problem in the priorart that a positioning server needs to perform signaling communicationwith each terminal device in a unicast transmission scenario can beavoided, thereby reducing signaling overheads.

Optionally, in another embodiment, the receiving unit is specificallyconfigured to receive the system message that is broadcast by thenetwork device and that carries the positioning assistance data.

Optionally, in another embodiment, the receiving unit is specificallyconfigured to receive a system message that is broadcast by the networkdevice and that carries second indication information, where the secondindication information is used to instruct the network device totransmit a third resource location for sending the positioningassistance data.

The processing unit is specifically configured to: obtain the secondindication information based on the system message; and obtain thepositioning assistance data at the third resource location based on thesecond indication information.

Optionally, in another embodiment, the receiving unit 1220 isspecifically configured to receive a system message that is broadcast bythe network device and that carries at least one first parameter.

The processing unit 1210 is specifically configured to detect a firstindication message at a first resource location based on the firstparameter received by the receiving unit, where the first indicationinformation is used to indicate a second resource location at which thenetwork device is to send the positioning assistance data.

The processing unit 1210 is further configured to obtain the positioningassistance data based on the second resource location indicated by thefirst indication information.

Therefore, in this embodiment of this application, the terminal devicereceives the system message broadcast by the network device, and obtainsthe positioning assistance data based on the system message. In thisway, a problem of low efficiency of transmitting existing centralizedpositioning assistance data can be resolved, and a problem in the priorart that a positioning server needs to perform signaling communicationwith each terminal device in a unicast transmission scenario can beavoided, thereby reducing signaling overheads.

Optionally, in another embodiment, the positioning assistance dataincludes differential satellite positioning assistance data.

Alternatively, in another embodiment, the positioning assistance data isephemeris data, real-time kinematic RTK data, or correction data.

It should be understood that the terminal device 1200 shown in FIG. 15can implement each process related to the terminal device in the methodembodiments of FIG. 4 to FIG. 12. Operations and/or functions of variousmodules in the terminal device 1200 are intended to implementcorresponding procedures in the method embodiments of FIG. 4 to FIG. 12.For details, refer to the descriptions in the method embodiments. Toavoid repetition, details are properly omitted herein.

Therefore, in this embodiment of this application, the terminal devicereceives the system message broadcast by the network device, and obtainsthe positioning assistance data based on the system message. In thisway, a problem of low efficiency of transmitting existing centralizedpositioning assistance data can be resolved, and a problem in the priorart that a positioning server needs to perform signaling communicationwith each terminal device in a unicast transmission scenario can beavoided, thereby reducing signaling overheads.

Because positioning assistance data is sent in a broadcast message or isindicated and sent through indication by using a broadcast firstparameter. In this case, UE may be in idle mode. If a cell in which theUE resides in idle mode is not a cell having relatively high strength orrelatively good quality, performance of the UE in receiving a systemmessage is relatively poor, causing a failure in obtaining thepositioning assistance data, and leading to a reduction in an overheadgain brought by broadcasting positioning assistance information.

To resolve this problem, a neighboring cell measurement mechanism of theUE in idle mode needs to be considered. In this way, the UE in idle modecan find a better neighboring cell in a timely manner, to reside in acell having better quality. The method is applicable to the UE in idlemode that receives the positioning assistance data, and is alsoapplicable to ordinary UE in idle mode. Herein, the embodiments aredescribed by using the ordinary UE as an example. Behavior of the UEreceiving the positioning assistance data is the same as that of theordinary UE.

To expand a coverage range of a cell, a base station may repeatedlyperform uplink and downlink sending, so that the UE can support datareceiving at a normal coverage level, and can implement data receivingat a coverage enhancement level. The receiving at the coverageenhancement level means that a terminal can receive a channel repeatedlysent by a base station, such as a synchronization channel, a broadcastchannel, a control channel, a data channel, and a reference symbol.

The solution of triggering neighboring cell measurement in a timelymanner includes the following several manners:

Manner 1: A signal strength trigger mechanism and a signal qualitytrigger mechanism are combined. Signal strength is an indicator similarto an RSRP/NRSRP/MRSRP/RSSI or the like. Signal quality is an indicatorsimilar to an RSRQ/NRSRQ/SNR, Ês/Iot, SNR, E_(c)/I_(o), or the like whenan interference factor is considered. In an existing trigger mechanismcombining signal strength and signal quality, measurement can be startedonly when a signal strength trigger threshold of a serving cell and asignal quality retransmission threshold of the serving cell are bothsatisfied. An advantage is reducing an opportunity of neighboring cellmeasurement, thereby reducing measurement consumption of the UE. In thisapplication, it is expected to avoid a problem that UE at a highcoverage level cannot trigger neighboring cell measurement to find abetter neighboring cell due to an excessively-low specified signalstrength threshold.

In this application, the trigger mechanism combining the signal strengthand the signal quality is:

If a signal strength threshold for measurement trigger does not satisfya threshold, UE detects whether a signal quality threshold satisfies athreshold. If the signal quality threshold satisfies the threshold, theUE starts neighboring cell measurement. The signal strength thresholdand the signal quality threshold may be at least one of a signalstrength threshold and a signal quality threshold of a serving cell, anda signal strength offset and a signal quality offset of the servingcell. The signal strength offset or the signal quality offset may be adifference between a current result and a previously stored result ormay be an offset configured in a network.

Alternatively, if a signal quality threshold does not satisfy athreshold, UE detects whether a signal strength threshold satisfies athreshold. If the signal strength threshold satisfies the threshold, theUE starts neighboring cell measurement. The signal strength thresholdand the signal quality threshold may be at least one of a signalstrength threshold and a signal quality threshold of a serving cell, anda signal strength offset and a signal quality offset of the servingcell. The signal strength offset or the signal quality offset may be adifference between a current result and a previously stored result ormay be an offset configured in a network.

Manner 2: Only a signal strength trigger mechanism is used, in which aplurality of thresholds are used, and different thresholds correspond toUE in different modes.

Signal strength may be at least one of a signal strength threshold of aserving cell and a signal strength offset of the serving cell. Thesignal strength offset may be a difference between a current result anda previously stored result or may be an offset configured in a network.

The UE in idle modes is classified into two types according to acoverage degree: UE at a high coverage level and UE hat a low coveragelevel. A signal strength trigger threshold is used for the UE at thehigh coverage level, and another signal strength trigger threshold isused for the UE at the low coverage level. A neighboring cellmeasurement trigger threshold of the UE at the low coverage level may beless than a neighboring cell measurement trigger threshold of the UE atthe high coverage level. The network or the terminal uses differentneighboring cell measurement trigger thresholds depending on differentcoverage statuses of UE.

The different thresholds may alternatively be set in other severalmanners.

Manner 1: Integer indication ranges of thresholds configured in thenetwork are the same, but step sizes used for the thresholds aredifferent. For example, a value of neighboring cell measurement based onsignal strength is configured as an integer (0, . . . , M₁). UE at thehigh coverage level may use a relatively small step size. For example,the step size is N₁. In this case, a value range represented by athreshold is an integer (0, . . . , M₁)*N₁ dB, where M₁ and N₁ arepositive integers.

For example, a value of neighboring cell measurement based on signalstrength is configured as an integer (0, . . . , M₁). UE at the lowcoverage level may use a relatively large step size, to obtain a largerthreshold configuration range. For example, the step size is N₂. In thiscase, a value range represented by a threshold is an integer (0, . . . ,M₁)*N₂ dB, where M₁ and N₂ are positive integers, and N₂>N₁.

Manner 2: Integer indication ranges of thresholds configured in thenetwork are different. For example, a value of neighboring cellmeasurement based on signal strength is configured as an integer (0, . .. , M₁). UE at the high coverage level may use a step size of N₁. Inthis case, a value range represented by a threshold is an integer (0, .. . , M₁)*N₁ dB, where M₁ and N₁ are positive integers.

For example, a value of neighboring cell measurement based on signalstrength is configured as an integer (0, . . . , M₂), to obtain a largerthreshold configuration range. UE at the low coverage level may use astep size of N₁. In this case, a value range represented by a thresholdis an integer (0, . . . , M₂)*N₁ dB, where M₂ and N₁ are positiveintegers, and M₂>M₁.

Manner 3: Ranges of thresholds configured in the network are the same,but UE at different coverage levels uses different thresholds. Forexample, a value of neighboring cell measurement based on signalstrength is configured as an integer (0, . . . , M₁). UE at the highcoverage level may use a step size of N₁. A configured neighboring cellmeasurement trigger threshold may be L₁, where L₁<M₁. In this case, athreshold integer is L₁*N₁ dB, where L₁, M₁, and N₁ are positiveintegers.

UE at the low coverage level may use a step size of N₁. A configuredneighboring cell measurement trigger threshold may be L₂, where L₂<M₁.In this case, a threshold integer is L₂*N₁ dB, where L₂, M₁, and N₁ arepositive integers, and L₂<L₁.

The coverage levels may be distinguished in two manners. In one manner,whether a coverage level is high or low is distinguished based on asignal and interference to noise ratio of a synchronization channel or areference symbol. For example, an SNR or an Es/Iot defined in a standardmay be used to distinguish better coverage and poorer coverage.Alternatively, the coverage levels may be distinguished by using signalstrength. The signal strength is an indicator similar to anRSRP/NRSRP/MRSRP/RSSI or the like.

The better coverage may include normal coverage, or normal coverage andintermediate coverage, coverage existing when a measurement value of UEis above a coverage distinguishing threshold. The poorer coverage iscoverage existing when a measurement value of UE is below the coveragedistinguishing threshold.

When there are a plurality of coverage distinguishing thresholds, aplurality of coverage distinguishing intervals such as a good coveragedistinguishing interval, an intermediate coverage distinguishinginterval, and a poor coverage distinguishing interval may be dividedaccording to a threshold interval.

Based on mobility, the UE in idle mode is divided into a mobile terminaland a non-mobile terminal. A signal strength trigger threshold is usedfor the mobile terminal, and another signal strength trigger thresholdis used for the non-mobile terminal. A neighboring cell measurementtrigger threshold of the non-mobile terminal may be less than aneighboring cell measurement trigger threshold of the mobile terminal.The network or the terminal uses a corresponding neighboring cellmeasurement trigger threshold based on mobility thereof.

It should be understood that “one embodiment” or “an embodiment”mentioned in the whole specification means that particular features,structures, or characteristics related to the embodiment are included inat least one embodiment of this application. Therefore, “in oneembodiment” or “in an embodiment” that appears throughput the wholespecification does not necessarily mean a same embodiment. Moreover, theparticular characteristic, structure or property may be combined in oneor more embodiments in any proper manner. It should be understood thatsequence numbers of the foregoing processes do not mean executionsequences in various embodiments of this application. The executionsequences of the processes should be determined according to functionsand internal logic of the processes, and should not be construed as anylimitation on the implementation processes of the embodiments of thisapplication.

In addition, the terms “system” and “network” may be usedinterchangeably in this specification. The term “and/or” in thisspecification describes only an association relationship for describingassociated objects and represents that three relationships may exist.For example, A and/or B may represent the following three cases: Only Aexists, both A and B exist, and only B exists. In addition, thecharacter “/” in this specification generally indicates an “or”relationship between the associated objects.

It should be understood that in the embodiments of this application, “Bcorresponding to A” indicates that B is associated with A, and B may bedetermined according to A. However, it should further be understood thatdetermining B according to A does not mean that B is determinedaccording to A only; that is, B may also be determined according to Aand/or other information.

A person of ordinary skill in the art may be aware that the units andsteps in the examples described with reference to the embodimentsdisclosed herein may be implemented by electronic hardware, computersoftware, or a combination thereof. To clearly describe theinterchangeability between the hardware and the software, the foregoinghas generally described compositions and steps of each example accordingto functions. Whether the functions are performed by hardware orsoftware depends on particular applications and design constraintconditions of the technical solutions. A person skilled in the art mayuse different methods to implement the described functions for eachparticular application, but it should not be considered that theimplementation goes beyond the scope of this application.

It may be clearly understood by a person skilled in the art that for thepurpose of convenient and brief description, for a detailed workingprocess of the foregoing system, apparatus, and unit, reference may bemade to a corresponding process in the foregoing method embodiments, anddetails are not described herein.

In the several embodiments provided in this application, it should beunderstood that the disclosed system, apparatus, and method may beimplemented in other manners. For example, the described apparatusembodiment is merely exemplary. For example, the unit division is merelylogical function division and may be other division in actualimplementation. For example, a plurality of units or components may becombined or integrated into another system, or some features may beignored or not performed. In addition, the displayed or discussed mutualcouplings or direct couplings or communication connections may beimplemented through some interfaces, indirect couplings or communicationconnections between the apparatuses or units, or electrical connections,mechanical connections, or connections in other forms.

The units described as separate parts may or may not be physicallyseparate, and parts displayed as units may or may not be physical units,may be located in one position, or may be distributed on a plurality ofnetwork units. Some or all of the units may be selected according toactual needs to achieve the objectives of the solutions of theembodiments of this application.

In addition, functional units in the embodiments of this application maybe integrated into one processing unit, or each of the units may existalone physically, or two or more units are integrated into one unit. Theintegrated unit may be implemented in a form of hardware, or may beimplemented in a form of a software functional unit.

With descriptions of the foregoing embodiments, a person skilled in theart may clearly understand that this application may be implemented byhardware, firmware or a combination thereof. When the present disclosureis implemented by software, the foregoing functions may be stored in acomputer-readable medium or transmitted as one or more instructions orcode in the computer-readable medium. The computer-readable mediumincludes a computer storage medium and a communications medium, wherethe communications medium includes any medium that enables a computerprogram to be transmitted from one place to another. The storage mediummay be any available medium accessible to a computer. The followingprovides an example but does not impose a limitation: Thecomputer-readable medium may include a RAM, a ROM, an EEPROM, a CD-ROM,or another optical disc storage or disk storage medium, or anothermagnetic storage device, or any other medium that can carry or storeexpected program code in a form of an instruction or a data structureand can be accessed by a computer. In addition, any connection may beappropriately defined as a computer-readable medium. For example, ifsoftware is transmitted from a website, a server or another remotesource by using a coaxial cable, an optical fiber/cable, a twisted pair,a digital subscriber line (DSL) or wireless technologies such asinfrared ray, radio and microwave, the coaxial cable, opticalfiber/cable, twisted pair, DSL or wireless technologies such as infraredray, radio and microwave are included in fixation of a medium to whichthey belong. For example, a disk (Disk) and disc (disc) used by thisapplication includes a compact disc (CD), a laser disc, an optical disc,a digital versatile disc (DVD), a floppy disk and a Blu-ray disc, wherethe disk generally copies data by a magnetic means, and the disc copiesdata optically by a laser means. The foregoing combination should alsobe included in the protection scope of the computer-readable medium.

In conclusion, what are described above are merely examples ofembodiments of the technical solutions of this application, but are notintended to limit the protection scope of this application. Anymodification, equivalent replacement, or improvement made withoutdeparting from the spirit and principle of this application shall fallwithin the protection scope of this application.

What is claimed is:
 1. A method comprising: receiving, by a network device, at least one positioning assistance data message from a positioning server that is configured to determine positions of terminal devices, wherein the at least one positioning assistance data message carries first positioning assistance data based on which positioning measurement is performed for positioning one or more terminal devices; determining, by the network device, second positioning assistance data according to the first positioning assistance data; and broadcasting, by the network device in response to receipt of the at least one positioning assistance data message, a system message to a terminal device, wherein the system message carries the second positioning assistance data for the terminal device to perform positioning measurement based on the first positioning assistance data.
 2. The method according to claim 1, wherein the system message comprises a system information block (SIB) or a positioning-dedicated SIB.
 3. The method according to claim 1, wherein the positioning assistance data message is a Long Term Evolution Positioning Protocol A (LPPa) message.
 4. The method according to claim 1, wherein the method further comprises: receiving, by the network device, a request message from the positioning server, wherein the request message requests third positioning assistance data from the network device; and sending, by the network device, a response message to the positioning server, wherein the response message carries the third positioning assistance data.
 5. An apparatus comprising: a receiver, configured to receive a positioning assistance data message sent by a positioning server that is configured to determine positions of terminal devices, wherein the positioning assistance data message carries first positioning assistance data based on which positioning measurement is performed for positioning one or more terminal devices; a processor, configured to determine second positioning assistance data according to the first positioning assistance data; and a transmitter, configured to broadcast, in response to receipt of the positioning assistance data message, a system message to a terminal device, wherein the system message carrying the second positioning assistance data for the terminal device to perform positioning measurement based on the first positioning assistance data.
 6. The apparatus according to claim 5, wherein the system message comprises a system information block (SIB) or a positioning-dedicated SIB.
 7. The apparatus according to claim 5, wherein the positioning assistance data message is a Long Term Evolution Positioning Protocol A (LPPa).
 8. The apparatus according to claim 5, wherein the receiver is configured to receive a request message from the positioning server, wherein the request message requests to obtain third positioning assistance data from the apparatus; and the transmitter is configured to send a response message to the positioning server, wherein the response message carries the third positioning assistance data.
 9. A method comprising: obtaining, by a positioning server configured to determine positions of terminal devices, first positioning assistance data based on which positioning measurement is performed for positioning one or more terminal devices; sending, by the positioning server, at least one positioning assistance data message to a network device, wherein the at least one positioning assistance data message comprises the first positioning assistance data; receiving, by the network device, the at least one positioning assistance data message; determining, by the network device, second positioning assistance data according the first positioning assistance data; and broadcasting, by the network device in response to receipt of the at least one positioning assistance data message, a system message, wherein the system message carries second positioning assistance data for a terminal device receiving the system message to perform positioning measurement based on the first positioning assistance data.
 10. The method according to claim 9, wherein the method further comprises: receiving, by the terminal device, the system message; obtaining, by the terminal device, the second positioning assistance data according to the first positioning assistance data; and performing, by a terminal device, positioning measurement based on the second positioning assistance data.
 11. The method according to claim 9, wherein the system message comprises a system information block (SIB) or a positioning-dedicated SIB.
 12. The method according to claim 9, wherein the positioning assistance data message is a Long Term Evolution Positioning Protocol A (LPPa) message.
 13. The method according to claim 9, wherein the method further comprises: receiving, by the positioning server, positioning measurement data from the terminal device; and determining, by the positioning server, a location of the terminal device based on the positioning measurement data.
 14. The method according to claim 9, wherein the method further comprises: receiving, by the network device from the positioning server, a request message, wherein the request message requests third positioning assistance data; and sending, by the network device, a response message to the positioning server, wherein the response message carries the third positioning assistance data.
 15. A system, comprising a positioning server and a network device, the positioning server configured to communicate with the network device, wherein, the positioning server is configured to obtain first positioning assistance data based on which positioning measurement is performed for positioning one or more terminal devices, send at least one positioning assistance data message to the network device, wherein the at least one positioning assistance data message comprises the first positioning assistance data; and the network device is configured to receive the at least one positioning assistance data message, determine second positioning assistance data according the first positioning assistance data, and broadcast, in response to receipt of the at least one positioning assistance data message, a system message, wherein the system message carries second positioning assistance data for a terminal device receiving the system message to perform positioning measurement based on the first positioning assistance data.
 16. The system according to claim 15, wherein the system further comprises the terminal device, and the terminal device is configured to communicate with the network device, wherein the terminal device is configured to receive the system message, obtain the second positioning assistance data according the first positioning assistance data and perform positioning measurement based on the second positioning assistance data.
 17. The system according to claim 15, wherein the system message comprises a system information block (SIB) or a positioning-dedicated SIB.
 18. The system according to claim 15, wherein the positioning assistance data message is a Long Term Evolution Positioning Protocol A (LPPa) message.
 19. The system according to claim 15, wherein, the positioning server is further configured to receive positioning measurement data from the terminal device, and determine a location of the terminal device based on the positioning measurement data.
 20. The system according to claim 15, wherein the network device is further configured to receive a request message from the positioning server, wherein the request message requests third positioning assistance data; and send a response message to the positioning server, wherein the response message carries the third positioning assistance data. 